As the World Cup approaches in the U.S., betting on yellow cards remains a controversial wager despite known vulnerabilities to match-fixing. Veteried betting consultants call this "the easiest market to manipulate" as a single player can control the outcome. Recent investigations in top leagues worldwide have led to criminal charges and lifetime bans for those involved in manipulating yellow cards for betting purposes.

Despite integrity concerns, at least three states—Mississippi, New Jersey and Oregon—plan to allow sportsbooks to offer yellow card betting during the World Cup. MLS Commissioner Don Garber has called these wagers "more susceptible to manipulation" and requested multiple states halt card markets. More than two dozen states have implemented statutes prohibiting betting on fouls or penalties.

Secondary markets like yellow card betting attracted $70 billion in stakes in 2024, according to the International Betting Integrity Association. The expected $6 billion wagered on non-score markets during the World Cup represents significant integrity risks. Recent cases, including Brazil's Lucas Paqueta being cleared of match-fixing charges, show how investigations can damage careers without concrete evidence.